Fire-alarm circuit.



PATBNTED JUNE 4, 1.9071

I. KITSEE. FIRE ALARM CIRCUIT. nruourox FILED 00131. 1902.

@noem to@ Q'ZI wth/Waeco ISIDOR KITSEE, PHILADELPHIA, PENNSYLVANIA.

MRE-ALARMv CIRCUIT.

vT all whom t may concern.-

Be it known that I, IsrDOR KITSEE, of the city and lcounty ofPhiladelphia, Stateof v Pennsylvania, have invented certain new anduseful Improvements in Fire-Alarm Circuits, of which the followingis aspecification.

My invention relates to an improvement in fire alarm circuits, anditsobject is to provide 4such circuits with a device capable of acting asagenerator of'electricity through the action of 'afhi'gh temperature dueto aconflagration.

In all fire alarm-circuits of'to-day, besides ythe circuit proper andapart from the alarms or annunclators, two distinctv devices have to tobe employed, one', the generator ol' electricity usually inthe form of aprimary'or secondary battery, and the other, a thermo-I static devicesometimes in the formhof two materials capable of different expansionand therefore capable of making or breaking the circuit in the presenceoi' a high temperature,

or fusible links alone or 1n connectionwithV spring or otherwiseactuateddevices.

To persons versed in the art, the difficulty of maintaining an eflicientprimary cell for a great length of time is well known, so also is wellknown the difficulty arising from thermostatic devices. And it is theaim of my invention to so combine both of these devices that a generatorof electricity and thermostat efficient just at the time when neededresults therefrom.

In Letters Patent No. 713,652, November 18, 1902, I described andclaimed a device which I called a thermo-electric generator and whichdevice is based on the principle, that a material solid andnon-conducting at low temperature and liquid and conducting at hightemperature is made to act, as the electrolyte in the presence of twoconductors I -capable of producing a difference of potentialin thepresence of such'electrolyte. I have, in this application, given as anexample, acetate of sodium as one of the materials which may be employedin suchcells; but where it is necessary t comparatively great strengthof current and should work uninterrupted for a comparative long periodand Where the cell may have to remain for months or even years inanonconducting state and may be only called on at very great intervals toact as generator, it is best to provide. such cells with a depolarizingmaterial whereby the action of the cell Specification of Letters Patent.

Application filed October 31, 1902. Serial No. 129,613.

at the cell shall give a Patented June 4, 1907.

is prolonged. Different electrodes can be employed with such cell andthe depolarizing material may consist of different metallic salts and Ihave illustrated in the drawing accompanying this specification, a cellwhich in practice has proven efficient enough for the purpose as stated.

Referring to the drawing -Figure 1 is a vertical sectional view of acell or generator called by methermo-electric cell or generator. Eig. 2is a vertical sectional view wherein a series of elements are combinedinto one receptacle so as to be capable of giving out a currentY ofhigher E. M. F. Fig. 3 is a diagrammatic view of a lire alarm circuitprovided with my device.

i In Fig. 1, A is the receptacle containing the material B designed toact asthe electrolyte when heated; C is a second material designed toact as an electrode 5 D is the nonconducting cover and E are means tosecure the cover tightly to the receptacle.

As said above; the cell illustrated has proven eflicient for allpractical purposes and the material of which this cell consisted was asfollows The outer receptacle A consisted of copper about 1/32 thick. Theinner surface of this copper receptacle was,

through electrolytic action,'prov1ded with a coating of oXid in thefollowing manner :f The receptacle was filled with a caustic or alkalinesolution (hydrate of potassium), a Zinc rod was then placed in thissolution and then the copper connected to the positive charging pole andthe zinc rod to the negative charging pole. Through the action of thecurrent, the copper becomes oxidized but no action will take place onthe zinc. After the oxidation was carried on to the necessary degree,the receptacle was emptied and dried and hydrate of potassium initssolid and dry state was then with the aid of heat liquefied 'and pouredinto the receptacle. As soon as the temperature of this solution becamelow enough, the hydrated potassium again solidified and formed a solidmass. T he zinc rod was placed, before such solidification took place,in a position as is illustrated. As long as the potassium salt retainedits high temerature and remained therefore in its iquid state, thecellgave at the beginning 1.10 volts and on short-circuit over 3amperes, but when solidification set in, no electro-motive force couldbe obtained and the cell acted not only as being in its inactive statebut acted as a IOO IOS

IIO

comparative high resistance and stopped the flow of the current in acircuit wherein 1 ampere was flowing at a pressure of 5 volts.

It will therefore be seen, that whereas this cell is efficient as agenerator of electricity as long as, through a high temperature, thematerial acting as the electrolyte is in its liquid state, it becomesfor all practical purposes inert as soon as, through a low temperature,solidification sets in.

I have given above a description of a cell consisting of copper and zincas electrodes, oxid of copper as depolarizer, and hydrated potash in 1tssolid state as the medium between these two electrodes, but it isobvious that other metals, other depolarizers, or other metallic saltsmay be employed without departing-from the scope of my invention.

In Fig. 2, F is the receptacle provided with the partitions F-l and theinsulating lining F-2. The solid material, designed to act aselectrolyte when heated, is designated by the letter Gr, and theelectrodes are designated by the letters H and I respectively.

The cell is made in the form well known as multiple-cell and theelectrodes straddle the partitions; these electrodes I prefer to -makeof a strip of copper, one-half of the length of this strip is providedwith thev oXid and the other halr` is provided with an electrodepositionof zinc, so that one part of the strip may act as the positive electrodein one compartment and the other part of the strip may act as negativein a second compartment.

The oxidation as well as the electro-deposition is made with the aid ofan electric current in an electrolytic cell. In the drawing I havedesignated the oxid of copper by the letter a and the coating of zinc bythe letter Z. The end electrode I may consist of Zinc alone and the endelectrode H may consist of copper, the surface of which is oxidized.

As it is intended to use these cells in connection with rire alarmcircuits it is necessary to make the receptacle F of a material capableof withstanding the action of heat, but capable of being raised to ahightemperature, and I therefore prefer to make this'receptacle of iron, andas iron is a conductor, it is necessary to line the same with anon-conducting material, such for instance as one of the well knowncements capable of withstanding the action of heat. As hydratedpotassium eagerly absorbs the moisture from the air when in contact withsame for a great length of time, it is necessary to close thereceptacle, and I therefore have provided the same with a non-conductingcovering designated in the drawing by the letter J g but thiscovering.may consist of iron if desired, and in this case, it has to be insulatedfrom the receptacle proper.

In Fig. 3, 1 and 2 are the main Ime-wires; 4 is an alarm and 3 arethe'thermo-electric devices such as above described.

Having now described my invention, what ISIDOR KITSEE.

Witnesses:

EDITH R. STILLEY, CHAs. KRESSENBACH'.

